Depitching apparatus



Filed May 15, 1936 3 Sheets-Sheet 1 Hal.

INVENTOR.

Orrin E. Andrus m ATTORNEY.

P 1940- o. E. ANDRUS DEPITCHING APPARATUS Filed May 15, 1936 3 Sheets-Sheet 2 INVENTOR Orrin E. Andrus {MM ATTORNEY.

P o. E. ANDRUS DEPITCHING APPARATUS Filed May 15, 1936 3 Sheets-Sheet 3 ,INVENTOR. Orrin E.Andrua K434;

ATTORNEY.

Patented Apr. 9, 1940 PATENT OFFICEJ nsrrrcnmc ArrAaA'ms Orrin E. Andrus, Milwaukee, Wis.,assignor to A. 0. SmithCorporation, Milwaukee, Wis a corporation of New York Application May is, 1930, Serial No. 7am

10mm. (chm-1st) The invention relates to apparatus for removing pitch or other coatings from the interior suriaces oi containers. is

An object of the invention is to provide im-' 6 proved methods and apparatus for removing coatings of soluble material from the inner surface of containers.

A more specific object oi the invention is to pro-- vide improved methods and apparatus for de- 1 pitching beer barrels. e

Other objects of the invention will be apparent from the following description and the accom- Pinyin! drawings, in which:

Figure 1 is a view of apparatus suitable for use with this invention, this view beingpartly in elegflgon and partlyin section on the line I-I of 2 is a topplan view of the apparatus of Fig. Fig. 3 is a vertical section on an enlarged scale of one of the spindles used for introducing vapor into the barrel, the section being taken along the line 3-3 at Fig. 2;

Fig. 4 is a view of a valve used in the operation 1' oi the apparatus showing its plunger in a position A diiierent from that shown in Fig. 1; and

Figs. 5 and 6 are enlarged views 01' a three-way j valve showing it in two diflerent positions 0! operation.

so In accordance with this invention, the pitch or solvent in stills I and 2 which may conveniently be cylindrical in shape as illustrated in the draw The stills may be heated in any convenient v In the drawings steam coils 8 are shown in 45 the-stills or the purpose of heating the solvent in the stills. Outlets l, furnished with valves 5, are

7 provided for draining the stills. Each still is desirably provided with a gauge glass 6 for indi* cating the liquid level, and with a safety device to 80 prevent explosions due to the building up of excessive pressure. Since the pressures involved are small, the safety device for still I may conveniently consist of a pipe I leading from the vapor space in this still to a trap 8 which is preferably mounted next to the condenser 9. The trap communicates at I Ii with the vapor space in'the condenser. Vapor flowing from the still to the trap condenses to a liquid which sets up a static pressure head and prevents further flow of vapor unless the pressure in the still becomes excessive, 6 in which case it can blow vapor through the liquid in the trap and through opening It into condenser 8. Another pipe II leads troinstill 2 to a similar trap mounted behind the one shown in the drawings. v 10 The traps serve not only as saietydevices but also as devices to maintain a substantially constant pressure in thestill. The rate of heat input .is so adjusted as to generate vapor somewhat more rapidly than it is used for depitching. This in'- sures that there will also be suflicient pressure. while excess pressure is prevented by escape of vapor through the traps. A manometer I2, or other suitable pressure gauge. may be provided ior'each still for showing the excess of vapor pressure above the atmospheric pressure.

Fromthestills I andi, vaporlines lland It provided with valves IS-and I6 respectively, lead to a solvent vapor header II which extends longitudinallyoi the apparatus. Condensate return 26 lines II and II provided with valves II and ii connectthe stills I and 2 respectively to a longitudinally extending condensate header 22.

For each barrel cleaning station there is provided a valve-28 opening into a spindle 24 upon 30 which the barrel II rests. Pipes it and 21 lead from valve 23 to the solvent vapor header l1 and the condensate header 22 respectively. 'Ihepipe '26 leading to the vapor header is desirably provided with a loop II to keep condensate from running into the vapor header. The pipe 21 should be so arranged as to permit drainage from the valve 23 to the condensate return header :2.

The'spindle 24, upon which rests the barrel to A be cleaned; is shown in detail in Fig. 3 It consists of an outer tube 29 tapered at its upper end to provide a conical seat 30 to engage with the metal II which defines the bung hole of the barrel 25'. Asbestos packing 32 is provided on the conical seat 30 to insure a tight joint. A separat- 5 conical seat-30 to the air vent tube N form an open centering cone to guide the barrel to the seat 30. Around the outside of the tube 29' a drip trough 36 is provided to catch any liquid or vapor which may leak through the joint between the barrel and the seat 30. A pipe 31 conveys the liquid or vapor caught by. the drip trough to a condenser 9 where the vapor is condensed.

The valve 23 has valve seats 38 and 39 and a plunger 40 with tapered ends adapted to seat against the valve seats 38 and 39. Pipe 4| leads from the valve 23 to the condenser 9, and also communicates by means of pipe 42 with the air vent tube 34. The valve plunger 40 is secured to rod 43 which passes through stuiling box 44. Operating lever 45 engages with the outer end of rod 43 and serves to move the plunger from oneposition to another. A valve seating spring 46 is provided to hold the plunger 40 tightly in engagement with the valve seat to which it is moved by the lever 45.

As shown in the drawings, the lever 45 is desirably continued to a position over the barrel 25 so that removal of the barrel from the spindle 24 is impeded or prevented while the operating lever is in such position as to admit solvent vapor from pipe 26 to the spindle.

The: condenser 3 is provided with cooling coils 41 for the circulation of water or other cooling medium and with a gauge glass 43. The condenser has a cover 43 provided with an opening 50 to permit the escape of air from the condenser and the introduction of liquid solvent into it. A pipe 5! leading from the bottom of the condenser communicates through valves 52 and 53 with condensate lines l3 and I9 leading to the stills l and 2. .A drain 54 with a valve 55 opens into the condenser 3 at a level slightly above the highest level reached by the pipe 5|, and another drain 56 with valve 31 is desirably provided at the bottom of the condenser to permit the complete drainage oi its contents.

A housing 58 is desirably provided to enclose the apparatus. The top of the housing forms a convenient working platform. It mayalso be desirable to include an insulating wall 59 to separate the hot stills from the cold condenser.

While the apparatus illustrated in Fig. 2 has four barrel cleaning stations, it is to be understood that the invention is not limited thereto and that any suitable number of stations may be used.

Trichlorethylene is a suitable solvent for removing many kinds of pitches from beer barrels, but other suitable solvents .or mixtures may be used if desired.

The two stills used in the apparatus provide a means for separating the solvent from the dissolved pitch without interrupting in any way the continuity of operation for cleaning barrels.

I Assuming that the apparatus is to be placed in operation. solvent is charged into the condenser 9 to iill'the lower portion and to run through pipe 3| and'valve 52 into still I. Valve 33 is closed to prevent solvent from running into still 2. When-the gauge glass ishows that a'sumcient quantity of solvent has been run into still I. the charging of solvent is discontinued. Valves l3 and 2| are closed; valves l3 and 23 are opened. Barrels to be cleaned are placed on the spindles 24 and the operating levers for those Spindles over whichbarrels have been placed are moved 'so as'to give them and valve plungers 43 the positions indicated'in Fig. 1.

Beer barrels have two openings; the bung hole and thetap hole. The bung hole is placed over the spindle while the tap hole is closed by a cork during depitching of the barrel.

Cooling water or other cooling medium is turned into coils 41 of the condenser 9, and steam into coils 3 of still I. Solvent vapor from still I passes through valve l5 and vapor line l3 to the vapor header I1, and from there through the pipes 26 to the individual barrel cleaning stations. Upon arriving at a station at which the valve plunger 40 is in the position indicated in Fig. l, the vapor then rises through spindle 24 to reach the interior of barrel 25. The air present in the barrel when it was inverted over the spindle is forced through air vent tube 34 and tubes 42 and 4| to the condenser 9 where solvent vapor entrained with the air is-condensed.

The provision of an air vent tube to permit the escape of air from the interior of the container is an important feature of the invention.

- Without a vent tube the solvent vapors act upon the pitch lining very much more slowly than when it is present. While the vent tube is provided primarily for the escape of air, in case vapor is being introduced into the container faster than it is being condensed therein, some vapor 'will also pass out through the vent tube and reach the condenser 9 where it will be condensed. Since the vapors of the solvents preferably used in connection with this invention are heavier than air, it is apparent that with the air vent tube located as in Fig. 1, the air in the container will be forced up while resting on the heavier solvent vapors and will be substantially all expelled if the air vent tube reaches nearly to the top of the barrel. This leads to rapid action of the solvent vapor upon all parts of the pitch lining.

The hot solvent vapor striking the interior of the barrel 25 is condensed and dissolves the pitch lining of the barrel.

The barrel is cold when placed upon the machine and because it is cold condenses the vapor impinging upon its inner surface. The condensation oi the vapor raises the temperature of the barrel, but since this is continually losing heat to its surroundings, vapor will continue to condense to make good the loss oi heat from the barrel. The speed with which pitch is removed has been materially increased by directing an air blast against the outer surface of the barrel. The .air blast removes heat from; the barrel more rapidly and results in an increased rate of condensation of vapor upon the inner surface of the barrel.

The condensed solvent and dissolved pitch run down the inner surface of the barrel and through the spindle 24 to the valve 23. The separating tube 33 located inside the'outer tube 23 of the spindle provides for a free passage of vapor up into the barrel unobstructed by condensate running down. From valve 23 the condensate runs through pipe 21 to the condensate header 22,

. and from there through valve 23 and pipe 13, back into still I.

. After the barrel has been subjected to the action of the solvent vapor for a sufllcient time to entirely dissolve and remove the pitch lining, the

operating lever 45 is moved back to throw the valve plunger 43 into the position shown in Fig. 4. In this position theplunger 43 seats on valve seat 33 and prevents the entrance of solvent vapor to the barrel. The cork closing the tap hole of the barrel is then removed. Since the vapor of such solvents as trichlorethylene carbon tetrachloride, or many other suitable solvents are materially heavier than air, the solvent vapor falls through the spindle 2i and pipe ll to the condenser 9 where the vapor is condensed. The barrel is at the same time filled with air drawn in through the tap hole. The barrel is .then removed from the spindle another barrel is placed onto the spindle and the cycle is repeated.

In using trichlorethylene for the removal of a high melting pitch from half barrels, it has been 'found that a treatment of the lining with solvent vapor for a period of about ten minutes is ordinarily sufficient to insure its complete removal. The barrel is allowed to remain upon the spindle for a further period or about one minute to permit the drainage of the solvent vapor from the barrel.

In some cases it may be desired to use the method and apparatus oi this invention for the depitching of barrels which have only one opening instead of two openings as is customary with beer barrels. In such cases the opening of the barrel is placed on the spindle 24.- As there is no tap hole to be opened, drainage of the solvent vapor from the barrel would be very slow if it were. not for the three-way valve 80. when the valve plunger 40 is in the position shown in Fig. l, the three-way valve 60 is in the position indicated in Fig. 5. When the valve plunger." is in the position indicated in Fig. 4, valve 60 is turned to the'position shown in Fig. 6. In this position, communication'with pipe 42 is shut ofl, and a slow stream of air from air line BI is passed up through air vent tube 34 to force the solvent vapor down through spindle 24 and into condenser 9. In many cases'it will be sufiicient if the valve 6|! merely opens to the atmosphere instead of to the air line 6|, but for greater rapidity of action the air line may be used. At most it should supply only a gentle stream of air as otherwise air and solvent vapor may be forced into and out of the condenser faster than the solvent can be condensed, resulting in an undesirable loss of solvent. For-the treatment of beer barrels with two openings, the valve '0 is not necessary as was previously pointed out. When valve 60 is provided it is desirably connected by mechanism not shown in the drawings to-lever 45 so as to be operated in synchronism with valveplunger 40.

Continued operation of the device results in the accumulation of dissolved pitch in still I. As

the pitch gradually accumulates in the still the temperature of the still should be gradually increased to maintain substantially the same vapor pressure. This has no deleterious effect upon the effectiveness of thedevice i'or depitching barrels since the pitch does not materially vaporize and only relatively pure solvent vapor is supplied to the spindles 24, but the dissolved pitch must of course be removed from the system from time to time. When it is desired to do this, valves 20 and 52 are closed while valves 2| and 53 are opened. Condensate from the condensate header 22 and condenser 9 is now returned to still 21nstead of to still I. When a suiilcient amount of condensate has collected in still 2 to cover the steam coils 3 in this. still, steam is admitted to these coils and valve It is opened. Both stills now supply vapor but the condensate is returned entirely to still 2. Continued operation results in the expulsion of practically all of the solvent from still I which will ultimately contain nothing but pitch. With valve I! left open the pitch in of time,'the pitch whichcollects in still 2 is removed in a similar manner. It will be noted that the distillation of solvent from the :pitch and the removal of the pitch does not interfere in any way with the continued use of the-machine for depitching barrels.

It is not infrequently round in depitching beer be. drained off at intervals and kept from accumulating to a sufllcient extent to enter into the stills. The presence of water vapor along with the solvent vapor materially reduces the rate at which the pitch is dissolved and removed from the barrel.

in the use of this apparatus. The loss is made ood by suitable additions of solvent to the conx denser.

I claim:

There will normally'be a slight loss of solvent 1. An apparatus-for removing a pitch or similar lining from the interior of a container which comprises a pair of stills ior boiling a solvent which dissolves the lining; means for heating the stills; vapor lines provided with valves to conduct solvent vapor from the stills to the container; condensate return lines provided with valves for conducting condensed solvent vapor and dissolved liningback from said container to the stills; control means connected to said lines to admit solvent vapor to the container and to permit condensed solvent to return to the stills when said control means have one operating position, and toprevent access of solvent vapor to the container or return of condensed solvent to the stills but to permit passage of solvent vapor from the container to a condenser when said means have a second operating position; a condenser; a pipe connection between said control means and said condenser; a vent tube to'conduct air and solvent vapor from the interior of the container to the condenser; and a pipe connection provided with valves to returnsolvent,

from the condenser to the stills.

2. In an-apparatus for the removal of a pitch or similar lining from the interior of a container, a spindle for admitting solvent vapor into the container, said spindle comprising an outer tube provided with a seat to engage with an opening rangement being adapted to permit tree communication between the air vent tube and the condenser when in one positiomand to shut oi the condenser and open tree communication between a source of air and the vent tube when in a din'erent position. Y

4. In anapparatus fortheremovalotapitch a-spindle for admitting solvent vapor to the inorslmilarliningirohrtheinteriorofacontainer terior or the container, saidspindle oomprlsing from the container, and a drip trough arranged outside the outer tube to catch vapor and solvent which may leakthrough the joint between a the spindle and the container and to deliver such vapor and condensed solvent to a tube which conveys it to a condenser where the vapor is condensed.

5. In an apparatus for the removal of a pitch or similar lining from the interior oia container, the combination of a spindle for introducing solvent vapor into the interior of the container and for draining away solvent condensed therein, a valve to admit solvent vapor to the container and to permit the drainage of condensed solvent therefrom when in one position and to prevent access of solvent vapor to the container when in a different position, and means to control the position of said valve, said control means being arranged to impede the removal of a container from the spindle when the valve is in position to admit solvent vapor to the spindle.

6. In an apparatus for the removal of a pitch or similar lining from the interior oi a container, a spindle for admitting solvent vapor into the container, said spindle comprising an outer tube provided with a seat to engage with an opening in the container and an inner tube disposed within said outer tube and arranged to separate solvent vapor entering the container from condensed solvent draining from it and a conduit in the spindle for removing air from the container as vapor enters the same.

'1. An apparatus for the removal of pitch or similar lining from the interior of a container which comprises two stills for boiling a solvent for the lining, means to conduct solvent vapor to the container, conduits connected with said means leading from each of said stills, means to control the flow of solvent vapor through said conduits, a vent for the escape of air from the container, means to conduct condensed solvent vapor from the container, conduits connected with said last named means leading to each of said stills, and means to control the flow of condensed solvent vapor through said last named conduits, said control means being disposed to establish communication alternately between said container and each of said two stills to permit removal of accumulated pitch from the inactive still without disrupting the continuity of opera-' tion of the apparatus. l. oaam E. ANDRUS. 

